Development and prospect of near-infrared spectroscopy-assisted schizophrenia diagnosis based on bibliometrics

In this editorial,we comment on the recent article by Fei et al exploring the field of near-infrared spectroscopy(NIRS)research in schizophrenia from a bibliometrics perspective.In recent years,NIRS has shown unique advantages in the auxiliary diagnosis of schizophrenia,and the introduction of bibliometrics has provided a macro perspective for research in this field.Despite the opportunities brought about by these technological developments,remaining challenges require multidi-sciplinary approach to devise a reliable and accurate diagnosis system for schizo-phrenia.Nonetheless,NIRS-assisted technology is expected to contribute to the division of methods for early intervention and treatment of schizophrenia.

Near-infrared brain functional characteristics of mild cognitive impairment with sleep disorders

BACKGROUND Mild cognitive impairment(MCI)has a high risk of progression to Alzheimer’s disease.The disease is often accompanied by sleep disorders,and whether sleep disorders have an effect on brain function in patients with MCI is unclear.AIM To explore the near-infrared brain function characteristics of MCI with sleep disorders.METHODS A total of 120 patients with MCI(MCI group)and 50 healthy subjects(control group)were selected.All subjects underwent the functional near-infrared spec-troscopy test.Collect baseline data,Mini-Mental State Examination,Montreal Cognitive Assessment scale,fatigue severity scale(FSS)score,sleep parameter,and oxyhemoglobin(Oxy-Hb)concentration and peak time of functional near-infrared spectroscopy test during the task period.The relationship between Oxy-RESULTS Compared with the control group,the FSS score of the MCI group was higher(t=11.310),and the scores of Pittsburgh sleep quality index,sleep time,sleep efficiency,nocturnal sleep disturbance,and daytime dysfunction were higher(Z=-10.518,-10.368,-9.035,-10.661,-10.088).Subjective sleep quality and total sleep time scores were lower(Z=-11.592,-9.924).The sleep efficiency of the MCI group was lower,and the awakening frequency,rem sleep latency period,total sleep time,and oxygen desaturation index were higher(t=5.969,5.829,2.887,3.003,5.937).The Oxy-Hb concentration at T0,T1,and T2 in the MCI group was lower(t=14.940,11.280,5.721),and the peak time was higher(t=18.800,13.350,9.827).In MCI patients,the concentration of Oxy-Hb during T0 was negatively correlated with the scores of Pittsburgh sleep quality index,sleep time,total sleep time,and sleep efficiency(r=-0.611,-0.388,-0.563,-0.356).It was positively correlated with sleep efficiency and total sleep time(r=0.754,0.650),and negatively correlated with oxygen desaturation index(r=-0.561)and FSS score(r=-0.526).All comparisons were P<0.05.CONCLUSION Patients with MCI and sleep disorders have lower near-infrared brain function than normal people,which is related to sleep quality.Clinically,a comprehensive assessment of the near-infrared brain function of patients should be carried out to guide targeted treatment and improve curative effect.

Functional near-infrared spectroscopy in non-invasive neuromodulation

Non-invasive cerebral neuromodulation technologies are essential for the reorganization of cerebral neural networks,which have been widely applied in the field of central neurological diseases,such as stroke,Parkinson’s disease,and mental disorders.Although significant advances have been made in neuromodulation technologies,the identification of optimal neurostimulation paramete rs including the co rtical target,duration,and inhibition or excitation pattern is still limited due to the lack of guidance for neural circuits.Moreove r,the neural mechanism unde rlying neuromodulation for improved behavioral performance remains poorly understood.Recently,advancements in neuroimaging have provided insight into neuromodulation techniques.Functional near-infrared spectroscopy,as a novel non-invasive optical brain imaging method,can detect brain activity by measuring cerebral hemodynamics with the advantages of portability,high motion tole rance,and anti-electromagnetic interference.Coupling functional near-infra red spectroscopy with neuromodulation technologies offe rs an opportunity to monitor the cortical response,provide realtime feedbac k,and establish a closed-loop strategy integrating evaluation,feedbac k,and intervention for neurostimulation,which provides a theoretical basis for development of individualized precise neuro rehabilitation.We aimed to summarize the advantages of functional near-infra red spectroscopy and provide an ove rview of the current research on functional near-infrared spectroscopy in transcranial magnetic stimulation,transcranial electrical stimulation,neurofeedback,and braincomputer interfaces.Furthermore,the future perspectives and directions for the application of functional near-infrared spectroscopy in neuromodulation are summarized.In conclusion,functional near-infrared spectroscopy combined with neuromodulation may promote the optimization of central pellral reorganization to achieve better functional recovery form central nervous system diseases.

Achieving broadband near-infrared luminescence in Cr^(3+)-Activated Y_(2)Mg_(2)Al_(2)Si_(2)O_(12)phosphors via multi-site occupancy

Cr^(3+)-activated near-infrared(NIR)phosphors are key for NIR phosphor-converted light emitting diodes(NIR pc-LED).While,the site occupancy of Cr^(3+)is one of the debates that have plagued researchers.Herein,Y2Mg2Al2-Si_(2)O1_(2)(YMAS)with multiple cationic sites is chosen as host of Cr^(3+)to synthesize YMAS:xCr^(3+)phosphors.In YMAS,Cr^(3+)ions occupy simultaneously Al/SiO4 tetrahedral,Mg/AlO6 octahedral,and Y/MgO8 dodecahedral sites which form three luminescent centers named as Cr1,Cr2,and Cr3,respectively.Cr1 and Cr2 relate to an intermediate crystal field,with transitions of^(2)E→^(4)A_(2)and^(4)T_(2)→^(4)A_(2)occurring simultaneously.As Cr^(3+)concentration increases,the^(4)T_(2)→^(4)A_(2)transition becomes more pronounced in Cr1 and Cr2,resulting in a red-shift and broadband emission.Cr3 consistently behaves a weak crystal field and exhibits the broad and long-wavelength emission.Wide-range NIR emission centering at 745 nm is realized in YMAS:0.03Cr^(3+)phosphor.This phosphor has high internal quantum efficiency(IQE?86%)and satisfying luminescence thermal stability(I423 K?70.2%).Using this phosphor,NIR pc-LEDs with 56.6 mW@320 mA optical output power is packaged and applied.Present study not only demonstrates the Cr^(3+)multi-site occupancy in a certain oxide but also provides a reliable approach via choosing a host with diverse cationic sites and local environments for Cr^(3+)to achieve broadband NIR phosphors.

Spatial sensitivity to absorption changes for various near-infrared spectroscopy methods:A compendium review

This compendium review focuses on the spatial distribution of sensitivity to localized absorption changes in optically diffuse media,particularly for measurements relevant to near-infrared spectroscopy.The three temporal domains,continuous wave,frequency domain,and time domain,each obtain different optical data types whose changes may be related to effective homogeneous changes in the absorption coefficient.Sensitivity is the relationship between a localized perturbation and the recovered effective homogeneous absorption change.Therefore,spatial sensitivity maps representing the perturbation location can be generated for the numerous optical data types in the three temporal domains.The review first presents a history of the past 30 years of work investigating this sensitivity in optically diffuse media.These works are experimental and theoretical,presenting one-,two-,and three-dimensional sensitivity maps for different Near-Infrared Spectroscopy methods,domains,and data types.Following this history,we present a compendium of sensitivity maps organized by temporal domain and then data type.This compendium provides a valuable tool to compare the spatial sensitivity of various measurement methods and parameters in one document.Methods for one to generate these maps are provided in Appendix A,including the code.This historical review and comprehensive sensitivity map compendium provides a single source researchers may use to visualize,investigate,compare,and generate sensitivity to localized absorption change maps.

Near-infrared spectroscopy in schizophrenia:A bibliometric perspective

BACKGROUND Compared with current methods used to assess schizophrenia,near-infrared spectroscopy(NIRS)has the advantages of providing noninvasive and real-time monitoring of functional activities of the brain and providing direct and objective assessment information.AIM To explore the research field of NIRS in schizophrenia from the perspective of bibliometrics.METHODS The Web of Science Core Collection was used as the search tool,and the last search date was April 21,2024.Bibliometric indicators,such as the numbers of publications and citations,were recorded.Bibliometrix and VOS viewer were used for visualization analysis.RESULTS A total of 355 articles from 105 journals were included in the analysis.The overall trend of the number of research publications increased.Schizophrenia Research was identified as an influential journal in the field.Kasai K was one of the most influential and productive authors in this area of research.The University of Tokyo and Japan had the highest scientific output for an institution and a country,respectively.The top ten keywords were“schizophrenia”,“activation”,“near-infrared spectroscopy”,“verbal fluency task”,“cortex”,“brain,performance”,“workingmemory”,“brain activation”,and“prefrontal cortex”.CONCLUSION Our study reveals the evolution of knowledge and emerging trends in the field of NIRS in schizophrenia.the research focus is shifting from underlying disease characteristics to more in-depth studies of brain function and physiological mechanisms.

Efficacy of multi-color near-infrared fluorescence with indocyanine green:A new imaging strategy and its early experience in laparoscopic cholecystectomy

BACKGROUND Near-infrared fluorescence imaging via using intravenous indocyanine green(ICG)has a wide range of applications in multiple surgical scenarios.In lapa-roscopic cholecystectomy(LC),it facilitates intraoperative identification of the biliary system and reduces the risk of bile duct injury.However,the usual single color fluorescence imaging(SCFI)has limitations in manifesting the fluorescence signal of the target structure when its intensity is relatively low.Moreover,sur-geons often experience visual fatigue.We hypothesized that a novel imaging stra-tegy,named multi-color fluorescence imaging(MCFI),could potentially address these issues by decreasing hepatic and background fluorescence pollution and improving biliary visualization.AIM To investigate the novel imaging strategy MCFI in LC.METHODS This was a single-center retrospective study conducted at Peking Union Medical College Hospital,Beijing,China.Patients who underwent LC from June 2022 to March 2023 by the same surgical team were enrolled.Demographic features,clinical and surgical information were collected.The clarity,visual comfort,and effectiveness of different imaging strategies were subjectively evaluated by surgeons.RESULTS A total of 155 patients were included,60 patients were in the non-ICG group in which only bright light illuminance without ICG was applied,60 patients were in the SCFI group,and 35 patients were in the MCFI group.No statist-ically significant differences were found in demographics or clinical history.Post-surgical complications were minimal in all 3 groups with no significant differences observed.MCFI improved the clarity of imaging and visual comfort.Clarity of imaging and visual comfort were improved with MCFI.CONCLUSION MCFI improves biliary visualization and reduces liver fluorescence contamination,which supports its routine use in LC.MCFI may also be a better choice than SCFI in other clinical settings.

A highly sensitive ratiometric near-infrared nanosensor based on erbium-hyperdoped silicon quantum dots for iron(Ⅲ) detection

Ratiometric fluorescent detection of iron(Ⅲ)(Fe^(3+))offers inherent self-calibration and contactless analytic capabilities.However,realizing a dual-emission near-infrared(NIR)nanosensor with a low limit of detection(LOD)is rather challenging.In this work,we report the synthesis of water-dispersible erbium-hyperdoped silicon quantum dots(Si QDs:Er),which emit NIR light at the wavelengths of 810 and 1540 nm.A dual-emission NIR nanosensor based on water-dispersible Si QDs:Er enables ratiometric Fe^(3+)detection with a very low LOD(0.06μM).The effects of pH,recyclability,and the interplay between static and dynamic quenching mechanisms for Fe^(3+)detection have been systematically studied.In addition,we demonstrate that the nanosensor may be used to construct a sequential logic circuit with memory functions.

Cortical activity in patients with high-functioning ischemic stroke during the Purdue Pegboard Test:insights into bimanual coordinated fine motor skills with functional near-infrared spectroscopy

After stroke,even high-functioning individuals may experience compromised bimanual coordination and fine motor dexterity,leading to reduced functional independence.Bilateral arm training has been proposed as a promising intervention to address these deficits.However,the neural basis of the impairment of functional fine motor skills and their relationship to bimanual coordination performance in stroke patients remains unclear,limiting the development of more targeted interventions.To address this gap,our study employed functional near-infrared spectroscopy to investigate cortical responses in patients after stroke as they perform functional tasks that engage fine motor control and coordination.Twenty-four high-functioning patients with ischemic stroke(7 women,17 men;mean age 64.75±10.84 years)participated in this cross-sectional observational study and completed four subtasks from the Purdue Pegboard Test,which measures unimanual and bimanual finger and hand dexterity.We found significant bilateral activation of the sensorimotor cortices during all Purdue Pegboard Test subtasks,with bimanual tasks inducing higher cortical activation than the assembly subtask.Importantly,patients with better bimanual coordination exhibited lower cortical activation during the other three Purdue Pegboard Test subtasks.Notably,the observed neural response patterns varied depending on the specific subtask.In the unaffected hand task,the differences were primarily observed in the ipsilesional hemisphere.In contrast,the bilateral sensorimotor cortices and the contralesional hemisphere played a more prominent role in the bimanual task and assembly task,respectively.While significant correlations were found between cortical activation and unimanual tasks,no significant correlations were observed with bimanual tasks.This study provides insights into the neural basis of bimanual coordination and fine motor skills in high-functioning patients after stroke,highlighting task-dependent neural responses.The findings also suggest that patients who exhibit better bimanual performance demonstrate more efficient cortical activation.Therefore,incorporating bilateral arm training in post-stroke rehabilitation is important for better outcomes.The combination of functional near-infrared spectroscopy with functional motor paradigms is valuable for assessing skills and developing targeted interventions in stroke rehabilitation.

Near-infrared cholangiography with intragallbladder indocyanine green injection in minimally invasive cholecystectomy

Laparoscopic cholecystectomy(LC)remains one of the most commonly performed procedures in adult and paediatric populations.Despite the advances made in intraoperative biliary anatomy recognition,iatrogenic bile duct injuries during LC represent a fatal complication and consist an economic burden for healthcare systems.A series of methods have been proposed to prevent bile duct injury,among them the use of indocyanine green(ICG)fluorescence.The most commonly reported method of ICG injection is the intravenous administration,while literature is lacking studies investigating the direct intragallbladder ICG injection.This narrative mini-review aims to assess the potential applications,usefulness,and limitations of intragallbladder ICG fluorescence in LC.Authors screened the available international literature to identify the reports of intragallbladder ICG fluorescence imaging in minimally invasive cholecystectomy,as well as special issues regarding its use.Literature search retrieved four prospective cohort studies,three case-control studies,and one case report.In the three case-control studies selected,intragallbladder near-infrared cholangiography(NIRC)was compared with standard LC under white light,with intravenous administration of ICG for NIRC and with standard intraoperative cholangiography(IOC).In total,133 patients reported in the literature have been administered intragallbladder ICG administration for biliary mapping during LC.Literature includes several reports of intragallbladder ICG administration,but a standardized technique has not been established yet.Published data suggest that NIRC with intragallbladder ICG injection is a promising method to achieve biliary mapping,overwhelming limitations of IOC including intervention and radiation exposure,as well as the high hepatic parenchyma signal and time interval needed in intravenous ICG fluorescence.Evidence-based guidelines on the role of intragallbladder ICG fluorescence in LC require the assessment of further studies and multicenter data collection into large registries.

Suppressing neuroinflammation using the near-infrared light emitted by (Sr,Ba)Ga_(12)O_(19): Cr^(3+) phosphor

Neurodegenerative diseases,such as Parkinson’s and Alzheimer’s diseases,affect the elderly worldwide and will become more prevalent as the global population ages.Neuroinflammation is a common characteristic of neurodegenerative diseases.By regulating the phenotypes of microglia,it is possible to suppress neuroinflammation and,in turn,help prevent neurodegenerative diseases.We report a noninvasive photonic approach to regulating microglia from overexcited M1/M2 to the resting M0 phenotype using a special near-infrared(NIR)light emitted by the SrGa_(12)O_(19)∶Cr^(3t) phosphor.The absorbance and internal and external quantum efficiencies of the optimal SreGa_(0.99)Cr_(0.01)_(12)O_(19) phosphor synthesized at 1400℃ for 8 h using 1%H_(3)BO_(3) t 1%AlF3 as flux are 53.9%,99.2%,and 53.5%;the output power and energyconversion efficiency of the LED device packaged using the optimal SrGa_(12)O_(19): Cr^(3+) phosphor driven at 20 mA reach unprecedentedly 19.69 mW and 37.58%,respectively.The broadband emission of the NIR LED device covers the absorption peaks of cytochrome c oxidase well,and the NIR light can efficiently promote the proliferation of microglia,produce adenosine triphosphate(ATP),reverse overexcitation,alleviate and inhibit inflammation,and improve cell survival rate and activity,showing great prospects for photomedicine application.

PREPARATION AND CHARACTERIZATION OF WATER-SOLUBLE NEAR-INFRARED EMITTING PbS QUANTUM DOTS

A new facile method for preparing water-soluble near-infrared （NIR）-emitting PbS quantum dots （QDs） is proposed by using N-acetyl-L-cysteine （NAC, a derivate of L-cysteine） as its stabilizer. The influence of the precursor Pb/S molar ratio, the Pb/NAC molar ratio, and the pH of original solution on optical properties is explored. Results show that aqueous PbS QDs with strong NIR fluorescence can be prepared and their photoluminescence emission peaks can be tuned from 895 nm to 970 nm. Studies indicate that such aqueous QDs have a potential application in biomedical imaging, especially in noninvasive in vivo fluorescence imaging. In addition, the resulting PbS QDs are further characterized by a transmission electron microscopy and X-ray diffraction analysis.

Classification of Guizhou Aspidistra Plants by Near-infrared Diffuse Reflectance Spectroscopy

[Objective] This study was conducted to establish a near-infrared diffuse reflectance spectroscopy of Guizhou Aspidistra plants. [Method] Twenty three batch- es of Guizhou Aspidistra plants including A. chishuiensis, A. spinula, A. Caespitosa, A. sichuanensis, A. ebianensis, A. retusa, A. guizhouensis and A. liboensis were subjected to drying, pulverization and sieving and then directly determined for near- infrared reflectance spectrums; and the plants in this genus were classified by clus- ter analysis and principal component analysis （PCA）. [Result] The near-infrared re- flectance spectrums of the 23 batches of Guizhou Aspidistra plants showed very high similarity. The spectrums were processed by first derivative method, and the spectral range of 4 000-7 500 cm-1 was selected as the analytical range. Cluster analysis and PCA were employed to mass spectrum variables of plants in Aspidis- tra, fewer new variables became the linear combination of primary variables, and small differences between different varieties were enlarged, thereby facilitating intu- itive classification of plants in this genus. [Conclusion] Near-infrared diffuse re- flectance spectroscopy is nondestructive and rapid for determination of solid sam- pies, and provides a new method for the classification of Guizhou Aspidistra plants combined by information processing techniques.

Fundus autofluorescence in central serous chorioretinopathy: association with spectral-domain optical coherence tomography and fluorescein angiography

and FA for identifying pathological abnormalities in CSC. The characteristics of IA AF in CSC were attributable to the modification of melanin in the RPE. IR- AIM: To evaluate the correlation among changes in fundus autofluorescence (AF) measured using infrared fundus AF (IR -AF) and short-wave length fundus AF (SW -AF) with changes in spectral -domain optical coherence tomography (SD -OCT) and fluorescein angiography (FA) in central serous chorioretinopathy (CSC). METHODS: Two hundred and twenty consecutive patients with CSC were included. In addition to AF, patients were assessed by means of SD -OCT and FA. Abnormalities in images of IA -AF, SW -AF, FA were analyzed and correlated with the corresponding outer retinal alterations in SD-OCT findings. RESULTS: Eyes with abnormalities on either IR-AF or SW-AF were found in 256 eyes (58.18%), among them 256 eyes (100%) showed abnormal IR -AF, but SW-AF abnormalities were present only in 213 eyes (83.20%). The hypo-IR-AF corresponded to accumulation of subretinal liquid, collapse of retinal pigment epithelium (APE) or detachment of APE with or without RPE leakage point in the corresponding area. The hyper -IR -AF corresponded to the area with loss of the ellipsoid portion of the inner segments and sub -sensory retinal deposits or focal melanogenesis under sensory retina. The hypo-SW-AF corresponded to accumulation of subretinal liquid or atrophy of RPE. The hyper -SW -AF associated with sub -sensory retinal deposits, detachment of RPE and focal melanogenesis. CONCLUSION: IR-AF was more sensitive than SW-AF AF should be used as a common diagnostic tool for identifying pathological lesion in CSC.

Role of wide-field autofluorescence imaging and scanning laser ophthalmoscopy in differentiation of choroidal pigmented lesions

·AIM:Toevaluatethe diagnostic properties of wide-field fundus autofluorescence(FAF) scanning laser ophthalmoscope(SLO) imaging for differentiating choroidal pigmented lesions.·METHODS: A consecutive series of 139 patients were included, 101 had established choroidal melanoma with13 untreated lesions and 98 treated with radiotherapy.Thirty-eight had choroidal nevi. All patients underwent a full ophthalmological examination, undilated wide-field imaging, FAF and standardized US examination. FAF images and imaging characteristics from SLO were correlated with the structural findings in the two patient groups.·RESULTS: Mean FAF intensity of melanomas was significantly lower than the FAF of choroidal nevi. Only 1out of 38 included eyes with nevi touched the optic disc compared to 31 out of 101 eyes with melanomas. In 18 out of 101 melanomas subretinal fluid was seen at the pigmented lesion compared to none seen in eyes with confirmed choroidal nevi. In 'green laser separation', a trend towards more mixed FAF appearance of melanomas compared to nevi was observed. The mean maximal and minimal transverse and longitudinal diameters of melanomas were significantly higher than those of nevi.·CONCLUSION: Wide-field SLO and FAF imaging may be an appropriate non-invasive diagnostic screening tool to differentiate benign from malign pigmented choroidal lesions.

Infrared autofluorescence, short-wave autofluorescence and spectral-domain optical coherence tomography of optic disk melanocytomas

AIM： To investigate the findings of infrared fundus autofluorescence（IR-AF） and spectral-domain optical coherence tomography（SD-OCT） in eyes with optic disc melanocytoma（ODM）.· METHODS： IR-AF findings and those of other ophthalmologic imaging examinations, including short-wave autofluorescence（SW-AF）, fluorescein angiography（FA）, fundus color photography, and SD-OCT of 8 eyes of 8 consecutive cases with ODM were assessed.·RESULTS： The ODMs in all cases（100%） presented similar IR-AF, SW-AF, and FA findings. On IR-AF images, ODMs showed outstanding hyper-AF with well-defined outline. On SW-AF images, the area of ODMs presented as hypo-AF. FA images revealed the leaking retinal telangiectasia on the surface of the ODMs. On SDOCT images in 8 cases（100%）, the ODMs were sloped with highly reflective surface, which were disorganized retina and optic nerve layers. In 7 cases（87.5%）, peripapillary choroids were involved. The melanocytomas of 8 cases（100%） presented as optically empty spaces. Vitreous seeds were found in one case（12.5%）.· CONCLUSION： IR-AF imaging may provide a new modality to evaluate the pathologic features of ODMs,and together with SW-AF imaging, offers a new tool to study biological characteristics associated with ODMs.SD-OCT is a valuable tool in delimitating the tumor extension and providing morphological information about the adjacent retinal tissue.

Comparison of autofluorescence and optical coherence tomography findings in acute and chronic central serous chorioretinopathy

AIM:To discuss and compare the fundus autofluorescence(FAF)and optical coherence tomography(OCT)in acute or chronic central serous chorioretinopathy(CSCR).METHODS:Medical records of 100 cases of CSCR were reviewed.Acute and chronic cases were evaluated according to the duration of decreased visual acuity,serous retinal detachment(RD)and focal leakage on fluorescein angiography(FA).Chi-square test was used for statistical analysis.RESULTS:Forty cases had acute and 60 cases had chronic CSCR.FAF showed focal hypo-autofluorescence in 34(85%)and iso-autofluorescence in 6(15%)of acute cases and hypo-autofluorescence in 51(85%),hyperautofluorescence in 6(10%)and iso-autofluorescence in3(5%)of chronic cases.OCT showed serous RD with distinct borders correlated with FAF findings(hypoautofluorescence)in all acute CSCR cases.In chronic CSCR group,OCT showed serous RD with indistinct borders correlated with FAF findings.The differences between the OCT and FAF findings of the two groups were significant(P=0.000).CONCLUSION:OCT and FAF findings can support the clinical observations in differential diagnosis of acute and chronic CSCR and help clinicians to evaluate retinal pigment epithelium,outer segments of photoreceptors and the components of serous RD.

Autofluorescence excitation-emission matrices for diagnosis of colonic cancer

AIM: To investigate the autofluorescence spectroscopic differences in normal and adenomatous coionic tissues and to determine the optimal excitation wavelengths for subsequent study and clinical application. METHODS: Normal and adenomatous coionic tissues were obtained from patients during surgery. A FL/FS920 combined TCSPC spectrofluorimeter and a lifetime spectrometer system were used for fluorescence measurement. Fluorescence excitation wavelengths varying from 260 to 540 nm were used to induce the autofluorescence spectra, and the corresponding emission spectra were recorded from a range starting 20 nm above the excitation wavelength and extending to 800 nm. Emission spectra were assembled into a three-dimensional fluorescence spectroscopy and an excitation-emission matrix (EEM) to exploit endogenous fluorophores and diagnostic information. Then emission spectra of normal and adenomatous coionic tissues at certain excitation wavelengths were compared to determine the optimal excitation wavelengths for diagnosis of coionic cancer. RESULTS: When compared to normal tissues, low NAD (P)H and FAD, but high amino acids and endogenous phorphyrins of protoporphyrin IX characterized the high-grade malignant coionic tissues. The optimal excitation wavelengths for diagnosis of coionic cancer were about 340, 380, 460, and 540 nm. CONCLUSION: Significant differences in autofluorescence peaks and its intensities can be observed in normal and adenomatous coionic tissues. Autofluorescence EEMs are able to identify coionic tissues.

Single-Crystalline In Ga As Nanowires for Room-Temperature High-Performance Near-Infrared Photodetectors

In Ga As is an important bandgap-variable ternary semiconductor which has wide applications in electronics and optoelectronics. In this work, single-crystal In Ga As nanowires were synthesized by a chemical vapor deposition method.Photoluminescence measurements indicate the In Ga As nanowires have strong light emission in near-infrared region. For the first time, photodetector based on as-grown In Ga As nanowires was also constructed. It shows good light response over a broad spectral range in infrared region with responsivity of 6.5×10~3 AW^(-1) and external quantum efficiency of 5.04×10~5%. This photodetector may have potential applications in integrated optoelectronic devices and systems.

Autofluorescence imaging endoscopy for identifi cation and assessment of inflammatory ulcerative colitis

AIM:To validate the clinical relevance of autofluores-cence imaging(AFI)endoscopy for the assessment of inflammatory ulcerative colitis(UC).METHODS:A total of 572 endoscopic images were se-lected from 42 UC patients:286 taken with white light imaging(WLI)and 286 with AFI from the same sites.WLI images were assessed for overall mucosal inflammation according to Mayo endoscopic subscore(MES),and for seven characteristic endoscopic features.Likewise,AFI photographs were scored according to relative abundance of red,green and blue color com-ponents within each image based on an RGB additive color model.WLI and AFI endoscopic scores from the same sites were compared.Histological evaluation of biopsies was according to the Riley Index.RESULTS:Relative to red(r=0.52,P<0.01)or blue(r=0.56,P<0.01)color component,the green color component of AFI(r=-0.62,P<0.01)corresponded more closely with mucosal inflammation sites.There were signif icant differences in green color components between MES-0(0.396±0.043)and MES-1(0.340± 0.035)(P<0.01),and between MES-1 and ≥ MES-2(0.318±0.037)(P<0.01).The WLI scores for "vascu-lar patterns"(r=-0.65,P<0.01),"edema"(r=-0.62,P<0.01),histology scores for "polymorphonuclear cells in the lamina propria"(r=-0.51,P<0.01)and "crypt architectural irregularities"(r=-0.51,P<0.01)showed correlation with the green color component of AFI.There were significant differences in green color components between limited(0.399± 0.042)and extensive(0.375±0.044)(P=0.014)polymorpho-nuclear cell inf iltration within MES-0.As the severity of the mucosal inflammation increased,the green color component of AFI decreased.The AFI green color com-ponent was well correlated with the characteristic en-doscopic and histological inflammatory features of UC.CONCLUSION:AFI has application in detecting inflammatory lesions,including microscopic activity in the co-lonic mucosa of UC patients,based on the green color component of images.